Cirsium discolor (Willd.) Spreng.
Common Name: PASTURE THISTLE
Coefficient of Conservatism: 4
Coefficient of Wetness: 5
Wetness Index: UPL
Physiognomy: Nt B-Forb

Meadows, fields, clearings, hillsides, river banks, sparsely forested sites; roadsides, vacant lots, pine plantations.

This species is very similar to C. altissimum. The heads of C. discolor run a little larger (involucre ca. 2.4–3.3 cm long in our material, compared with 2–2.7 cm in C. altissimum), but precise measurements are hard to determine. The white-flowered form [f. albiflorum (Britton) House] has been collected in Calhoun, Lenawee, Oakland, and Washtenaw Cos.

Locations

Bay County
Berrien County
Branch County
Calhoun County
Cass County
Emmet County
Genesee County
Grand Traverse County
Hillsdale County
Jackson County
Kalamazoo County
Kent County
Lenawee County
Livingston County
Macomb County
Mecosta County
Menominee County
Midland County
Monroe County
Newaygo County
Oakland County
St. Clair County
Tuscola County
Washtenaw County
Wayne County

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 13, 2017. http://michiganflora.net/species.aspx?id=285.